In the name of Allah most gracious most merciful
Assalaamu alaykum wa rahmatuallahi wa barakatahu
Every good action or deed should be started with reciting Bismillah .
Said O chief! Surely an honorable letter has been delivered to me Surely it is from Sulaiman, and surely it is in the name of Allah, Most Gracious, Most Merciful;
[Al-Quran, Surah Al-Naml, Ayahs 29-30]
In this section we will quote some Authentic Traditions of the Prophet Muhammad (saw) regarding Bismillah - In the name of Allah.
Saying Bismillah Is Recommended Before Eating:
The Prophet (saw) said, "Say Bismillah, eat with your right hand and eat what is in front of you."
[Bukhari 7/88, Muslim 2/207, Ahmad 17/92, Muwatta Malik 10/32 and Ibn Majah 1/557]
Saying Bismillah Is Recommended When Drinking Water:
Ibn Abbas (ra) reported that the Messenger of Allah (saw) said,
"Do not drink in one gulp like a camel, but in two or three [Gulps]. Mention the Name of Allah when you start drinking and praise Him after you have finished Drinking.''
[Fath al-Bari 12/197 and Al-Trimidhi]
Saying Bismillah Is Recommended At The Beginning Of Ablution:
The Prophet (saw) said, "Make Wudu [Ablution] in the name of Allah"
[An-Nasai 1/11 and Ibn Khuzaimah 1/84]
Saying Bismillah Is Recommended Before Having Sexual Intercourse with one's wife:
The Prophet (saw) said,
"If anyone of you, when having sexual intercourse with his wife, says: In the name of Allah. O Allah! Protect us from Satan and also protect what you grant us [i.e. Coming offspring] from Satan and if it is destined that they should have a child, then Satan will never be able to harm him."
[Sahih Bukhari 7/94 and Sahih Muslim 2/1058]
Saying Bismillah Is Recommended When Entering The House:
Jabir (ra) said: I heard the Messenger of Allah (saw) saying,
"If a person mentions the Name of Allah upon entering his house or eating, Satan says, addressing his followers: `You will find no where to spend the night and no dinner.' But if he enters without mentioning the Name of Allah, Satan says [To his followers]; `You have found [A place] to spend the night in, and if he does not mention the Name of Allah at the time of eating, Satan says: `You have found [A place] to spend the night in as well as food."
[Sahih Muslim 2/206]
Saying Bismillah Is Recommended When Leaving The House:
The Messenger Of Allah (saw) said,
"If anyone of you when leaving the house says In the name of Allah, I trust in Allah, there is no power and might except from Allah. Your needs shall be fulfilled, you shall be saved from difficulties and hardships. Shaitaan hearing these words leaves him."
Say Bismillah At The Time When Slaughtering An Animal:
Anas (ra) reported that the Messenger (saw) of Allah sacrificed two horned rams of white color with black markings over them. He also stated: I saw him sacrificing them with his own hand and saw him placing his foot on their sides, and recited in the name of Allah and Glorified Him [Bismillah Allaahu Akbar]
[Bukhari 7/133, Muslim 2/181, Abu Dawud 3/230, An-Nasai 7/231, Al-Trimidhi 5/76, Ibn Majah 2120]
Saying Bismillah Is Recommended When Fighting For The Cause Of Allah:
The Messenger of Allah (saw) said, "Fight in the name of Allah and in the way of Allah"
[Sahih Muslim 2/69]
Saying Bismillah Is Recommended Before Entering The Toilet:
The Prophet Of Allah (saw) said
"When you enter the toilet you should say, In the Name of Allah, I seek protection in you from unclean spirits, male and female."
[Abu Dawud 4/264, Ahmad 2/389 and Fath Al-Bari 1/254]
Saying Bismillah Is Recommended Because It Causes Humiliation To The Shaitaan:
Abul Malih said: I was riding on a mount behind the Prophet (saw). It stumbled. Thereupon I said: May the devil perish! He said: Do not say: May the devil perish! For if you say that, he will swell so much so that he will be like a house, and say: By my power.
But say Bismillah for when you say that, he will diminish so much so that he will be like a fly.
[An-Nasai 6/142, Ahmad 5/59 and Abu Dawud 4946]
Saying Bismillah Is Recommended When Night Falls:
Allah's Apostle (saw) said, "When night falls stop your children from going out, for the devils spread out at that time. But when an hour of the night has passed, release them and close the doors and mention Allah's Name, for Satan does not open a closed door.
Tie the mouth of your water-skin and mention Allah's Name; cover your containers and utensils and mention Allah's Name. Cover them even by placing something across it, and extinguish your lamps. "
[Bukhari 7/527 and Abu Dawud 3722]
Saying Bismillah Is Recommended When Placing The Body Of The Deceased In The Grave:
The Prophet of Allah (saw) said, "When you are lowering the deceased in the grave you should say In the name of Allah and in accordance to the Sunnah of the Messenger of Allah."
[Ahmad 8/58 and Al-Hakim 1/366]
The Virtue Of Saying Bismillah:
Uthman bin Abu al-As Al-Thaqafi reported that he made a complaint of pain to Allah's Messenger (saw) that he felt in his body at the time he had become Muslim. Thereupon Allah's Messenger (saw) said: Place your hand at the place where you feel pain in your body and say in the name of Allah three times and seven times I seek refuge with Allah and with His Power from the evil that I find and that I fear. [Muslim 2/280]
It Is Recommended When Writing A Letter Bismillah Should Also Be Written:
Abu Sufyan said that the contents of the letter were as follows:
"In the name of Allah the Beneficent, the Merciful, [This letter is] from Muhammad the slave of Allah and His Apostle to Heraclius the ruler of Byzantine. Peace be upon him, who follows the right path. Furthermore I invite you to Islam, and if you become a Muslim you will be safe, and Allah will double your reward, and if you reject this invitation of Islam you will be committing a sin by misguiding your peasants."
[Bukhari 4/191, Muslim 2/91, Al-Trimidhi 7/500]
Allah knows best.